#1 Preheat oven to 350°F. Line baking sheet with parchment paper. #2 In a large bowl add butter, sugars, egg, vanilla extract. Stir until well combined. #3 Mix in flour, cornstarch, baking soda and salt. Next, fold in the chocolate chips. #4 Using an ice cream scooper, place dough balls onto the baking sheet, and spread evenly. Bake for 10 to 12 minutes, or until edges are light golden brown. #5 Allow cookies to cool on the baking sheet for about 5 minutes before serving.